Unobservable Privacy-Preserving Routing in MANET

Privacy-preserving routing is crucial for some ad hoc networks that require stronger privacy protection. A number of anonymous routing schemes have been proposed for ad hoc networks in recent years, and they provide different level of privacy protection at different cost. These schemes are more scalable to network size, but require more computation effort. However, existing schemes provide only anonymity and unlinkability, while unobservability is never considered or implemented by now. An obvious drawback in existing schemes is that packets are not protected as a whole.